When I was a kid, it seemed to me that the only window cleaner you could get was Windolene, and that, as I remember, was a vivid lilac colour. I even remember a school teacher pointing out that it would be impossible to market a non-lilac-coloured window cleaner, because "everyone knows" that window cleaner is lilac.
Well now the lilacs are out in my garden, perfuming the air, and distracting attention from the dying tomato plants. But I can't stop thinking about window cleaner when I see them.
Some Iris are out too, along with Paeony and Dicentra, also known, (in its more popular red and white form), as bleeding heart.